MAX1641EEE+ Maxim Integrated Products, MAX1641EEE+ Datasheet - Page 8

• Manufacturer Part Number: MAX1641EEE+
• Description: IC SW-MODE CUR SOURCE ADJ 16QSOP
• Manufacturer: Maxim Integrated Products

Specifications of MAX1641EEE+

• Function: Charge Management
• Voltage - Supply: 5.5 V ~ 26 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-SSOP (0.150", 3.90mm Width)
• Number Of Outputs: 1
• Duty Cycle (max): 100 %
• Output Voltage: 2 V to 24 V
• Mounting Style: SMD/SMT
• Switching Frequency: 500 KHz
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Synchronous Pin: No
• Topology: Buck
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The voltage at SET is given by:
where V
desired output current level.
Adjustable-Output, Switch-Mode
Current Source with Synchronous Rectifier
Table 1. Selecting Output Current Levels
Figure 2. Adjusting the Output Current Level
Figure 3a. Setting the Maximum Output Voltage Level
8
D1
0
0
1
1
R1 = R2 (V
_______________________________________________________________________________________
DO
0
1
0
1
REF
MAX1640
Pulse-Trickle
Fast Charge
= 2V and V
REF
R1
R2
Top-Off
MODE
OFF
/ V
TERM
CS+
CS-
SET
-1 ); 10kΩ < R2 < 300kΩ
SET
REF
SET
OUTPUT CURRENT (A)
0
V
V
12.5% duty cycle
V
SET
SET
REF
MAX1640
MAX1641
is proportional to the
/ (13.3R
/ (13.3R
/ (13.3R
L
R
R3
R4
SENSE
SENSE
SENSE
SENSE
BATT
)
)
)
The MAX1640/MAX1641 are specified for V
between 0V and V
increases linearly (with reduced accuracy) until it
clamps at V
Pulling D0 low and D1 high selects pulse-trickle mode.
This current equals V
on for 12.5% of the period set by R
current maintains full charge across the battery and
can slowly charge a cold battery before fast charging
commences.
Pulling D0 and D1 low turns off the P-channel FET and
hence the output current flow. This mode also controls
end of charge and protects the battery against exces-
sive temperatures.
The maximum output voltage should be programmed to
a level higher than the output/battery voltage (I
R
and ground (Figure 3) sets the voltage at TERM. Once
the voltage at TERM exceeds the reference, the internal
comparator turns off the P-channel FET, terminating
current flow. Select R4 in the 10kΩ to 500kΩ range.
R3 is given by:
Figure 3b. Setting the Maximum Output Voltage Level
LOAD
Off Mode: Turning Off the Output Current
). An external resistor-divider between the output
PERIOD = 3.2 x 10
SET
Pulse-Trickle Mode: Selecting the
R3 = R4 ((V
MAX1641
≈ 4V.
Setting the Maximum Output
REF
TERM
. For V
SET
CS+
CS-
OUT
/ (13.3R
Pulse-Trickle Current
SET
-7
/ V
x R
TERM
> V
R
SENSE
TOFF
BATT
L
SENSE
REF
TOFF
Voltage Level
) -1)
(sec)
, output current
) and remains
. Pulse-trickle
R3
R4
LOAD
SET
x